Commit 5553ba2b authored by Edmund Nadolski's avatar Edmund Nadolski Committed by Dan Williams
Browse files

isci: replace isci_timer list with proper embedded timers 



Rather than preallocating a list of timers and doling them out at runtime,
embed a struct timerlist in each object that needs one.  A struct sci_timer
interface is introduced to manage the timer cancellation semantics which
currently need to guarantee the timer is cancelled while holding
spin_lock(ihost->scic_lock).  Since the timeout functions also need to acquire
the lock it currently prevents the driver from using del_timer_sync() for
runtime cancellations.

del_timer_sync() is used however before the objects go out of scope.

Signed-off-by: default avatarEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 9269e0e8

drivers/scsi/isci/host.c

+7 −0
Original line number Diff line number Diff line
@@ -1359,6 +1359,13 @@ void isci_host_deinit(struct isci_host *ihost) 


	wait_for_stop(ihost);

	scic_controller_reset(&ihost->sci);



	/* Cancel any/all outstanding port timers */

	for (i = 0; i < ihost->sci.logical_port_entries; i++) {

		struct scic_sds_port *sci_port = &ihost->ports[i].sci;

		del_timer_sync(&sci_port->timer.timer);

	}



	isci_timer_list_destroy(ihost);

}

drivers/scsi/isci/isci.h

+33 −0
Original line number Diff line number Diff line
@@ -551,4 +551,37 @@ extern unsigned char max_concurr_spinup; 
irqreturn_t isci_msix_isr(int vec, void *data);

irqreturn_t isci_intx_isr(int vec, void *data);

irqreturn_t isci_error_isr(int vec, void *data);



/*

 * Each timer is associated with a cancellation flag that is set when

 * del_timer() is called and checked in the timer callback function. This

 * is needed since del_timer_sync() cannot be called with scic_lock held.

 * For deinit however, del_timer_sync() is used without holding the lock.

 */

struct sci_timer {

	struct timer_list	timer;

	bool			cancel;

};



static inline

void sci_init_timer(struct sci_timer *tmr, void (*fn)(unsigned long))

{

	tmr->timer.function = fn;

	tmr->timer.data = (unsigned long) tmr;

	tmr->cancel = 0;

	init_timer(&tmr->timer);

}



static inline void sci_mod_timer(struct sci_timer *tmr, unsigned long msec)

{

	tmr->cancel = 0;

	mod_timer(&tmr->timer, jiffies + msecs_to_jiffies(msec));

}



static inline void sci_del_timer(struct sci_timer *tmr)

{

	tmr->cancel = 1;

	del_timer(&tmr->timer);

}



#endif  /* __ISCI_H__ */

drivers/scsi/isci/port.c

+18 −21
Original line number Diff line number Diff line
@@ -926,17 +926,19 @@ bool scic_sds_port_link_detected( 
	return true;

}



/**

 * This method is provided to timeout requests for port operations. Mostly its

 *    for the port reset operation.

 *

 *

 */

static void scic_sds_port_timeout_handler(void *port)

static void port_timeout(unsigned long data)

{

	struct scic_sds_port *sci_port = port;

	struct sci_timer *tmr = (struct sci_timer *)data;

	struct scic_sds_port *sci_port = container_of(tmr, typeof(*sci_port), timer);

	struct isci_host *ihost = scic_to_ihost(sci_port->owning_controller);

	unsigned long flags;

	u32 current_state;



	spin_lock_irqsave(&ihost->scic_lock, flags);



	if (tmr->cancel)

		goto done;



	current_state = sci_base_state_machine_get_state(&sci_port->state_machine);



	if (current_state == SCI_BASE_PORT_STATE_RESETTING) {
@@ -965,6 +967,9 @@ static void scic_sds_port_timeout_handler(void *port) 
			"%s: SCIC Port 0x%p is processing a timeout operation "

			"in state %d.\n", __func__, sci_port, current_state);

	}



done:

	spin_unlock_irqrestore(&ihost->scic_lock, flags);

}



/* --------------------------------------------------------------------------- */
@@ -1259,7 +1264,6 @@ static void scic_sds_port_ready_substate_configuring_exit(struct sci_base_state_ 
enum sci_status scic_sds_port_start(struct scic_sds_port *sci_port)

{

	struct scic_sds_controller *scic = sci_port->owning_controller;

	struct isci_host *ihost = scic_to_ihost(scic);

	enum sci_status status = SCI_SUCCESS;

	enum scic_sds_port_states state;

	u32 phy_mask;
@@ -1280,14 +1284,6 @@ enum sci_status scic_sds_port_start(struct scic_sds_port *sci_port) 
		return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;

	}



	sci_port->timer_handle =

		isci_timer_create(ihost,

				  sci_port,

				  scic_sds_port_timeout_handler);



	if (!sci_port->timer_handle)

		return SCI_FAILURE_INSUFFICIENT_RESOURCES;



	if (sci_port->reserved_rni == SCU_DUMMY_INDEX) {

		u16 rni = scic_sds_remote_node_table_allocate_remote_node(

				&scic->available_remote_nodes, 1);
@@ -1390,7 +1386,7 @@ static enum sci_status scic_port_hard_reset(struct scic_sds_port *sci_port, u32 
	if (status != SCI_SUCCESS)

		return status;



	isci_timer_start(sci_port->timer_handle, timeout);

	sci_mod_timer(&sci_port->timer, timeout);

	sci_port->not_ready_reason = SCIC_PORT_NOT_READY_HARD_RESET_REQUESTED;



	port_state_machine_change(sci_port,
@@ -1757,14 +1753,14 @@ static void scic_sds_port_resetting_state_exit(struct sci_base_state_machine *sm 
{

	struct scic_sds_port *sci_port = container_of(sm, typeof(*sci_port), state_machine);



	isci_timer_stop(sci_port->timer_handle);

	sci_del_timer(&sci_port->timer);

}



static void scic_sds_port_stopping_state_exit(struct sci_base_state_machine *sm)

{

	struct scic_sds_port *sci_port = container_of(sm, typeof(*sci_port), state_machine);



	isci_timer_stop(sci_port->timer_handle);

	sci_del_timer(&sci_port->timer);



	scic_sds_port_destroy_dummy_resources(sci_port);

}
@@ -1831,7 +1827,8 @@ void scic_sds_port_construct(struct scic_sds_port *sci_port, u8 index, 
	sci_port->reserved_rni = SCU_DUMMY_INDEX;

	sci_port->reserved_tci = SCU_DUMMY_INDEX;



	sci_port->timer_handle = NULL;

	sci_init_timer(&sci_port->timer, port_timeout);



	sci_port->port_task_scheduler_registers = NULL;



	for (index = 0; index < SCI_MAX_PHYS; index++)

drivers/scsi/isci/port.h

+2 −4
Original line number Diff line number Diff line
@@ -139,10 +139,8 @@ struct scic_sds_port { 
	 */

	struct scic_sds_controller *owning_controller;



	/**

	 * This field contains the port start/stop timer handle.

	 */

	void *timer_handle;

	/* timer used for port start/stop operations */

	struct sci_timer	timer;



	/**

	 * This field is the pointer to the port task scheduler registers

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